18 This study followed the guidelines recommended by Guillemin selleck inhibitor et al.10 thus minimizing the occurrences of biases and inclinational results. This methodology made the Brazilian version of the KSS fit for application in Brazilian patients, thus making it possible to measure clinical outcomes and treatments at the same time, or through a particular follow-up. As regards semantic validity, the Brazilian adaptation of the Knee Evaluation Scale, translated and culturally adapted, demonstrated excellent semantic and conceptual equivalence, according to the results of the inter-evaluator analysis, whereas the entire process was based on the studies of Ciconelli,19 Duarte et al.17 and Guillemin et al.
10 As we were able to observe in the studies that performed the validation, it is important to supplement the translation with the sociocultural adaptation of the version for the language, in this case, Portuguese, to allow the scale to be better evaluated in the country. In the translation and validation of the original version of the KSS, only one alteration was made in the knee function score, in the item walking, in which the distance that is evaluated in Manhattan city blocks, in which a block is equal to 80 meters, was modified to distance in meters. This change is necessary as it corresponds more closely to the Brazilian situation, since blocks in Brazil are not standardized in all cities with the same measurements in meters. The sample of 70 patients divided by the number of items of the scale (5 – deductions are not considered) results in 14 subjects per item.
Kelinger20 recommends, as a general rule for the validation of instruments, the use of the largest possible sample and suggests 10 subjects per item of the instrument. In this study the participants conducted the Kaiser-Meyer-Olkin Measure of Sampling Adequacy (KMO) study, which measures the adequacy of data for the factor analysis. The KMO resulted in 0.962, which indicates that the data were optimal for the factor analysis, i.e., the sample size was adequate.11 Reliability was evaluated by internal consistency, estimated by Cronbach’s alpha coefficient, for each evaluation period and in each score. We evaluated the contribution of each item to the reliability of the domains. This index can range from 0 to 1 and the higher this value, the greater the reliability of the scale.
11 All the correlations between and among items in the periods were positive and significantly different from zero, which indicates that it makes sense to form a scale with these items, as they Carfilzomib measure the same attribute: self-efficacy. The inter-evaluator reliability can be observed in Tables 2 and and3,3, in which the applications of the Knee Evaluation Scale (Knee Score and Knee Function Score) performed by evaluator 1 (questionnaire in English) and evaluator 2 (questionnaire in Portuguese) were compared in the preoperative period and at three and six months postoperatively.